Method of cervical videoscope with detachable camera

ABSTRACT

A simple yet highly useful cervical videoscope has been provided which can easily be used by the doctor to examine the cervix and vagina for cancerous lesions or other abnormalities. Also, because of the small size of the video camera unit there is sufficient space between the video camera unit and the blades of the speculum for inserting forceps and other instruments that may need to be used. By using the cervical videoscope in combination with a monochromator the physician can step the wavelength of light from one end of the light spectrum to the other until he observes florescence which identifies abnormal cells. Thereupon, he can destroy the cells by use of a laser beam. When he observes that no more florescence,is occurring, then he can discontinue the operation of the laser, knowing that the lesion has been completely eradicated. Also, a channel for drawing a suction to remove smoke created by the destruction of the lesion can be provided. The video camera unit also is adjustable along a guide on the fixed blade of the speculum to focus it. The video camera unit can be removed from the speculum and inserted into a sterile sheath for reinsertion into the vagina for examination for lesions and areas covered by the speculum blade. It can also be inserted into the colon and other body passageways where lesions are suspected. The video camera unit can be removed from the sheath, resterilized or disinfected and reattached to a sterile speculum for use with another patient.

This application is a division of U.S. Ser. No. 695,727, filed May 6,1991, now U.S. Pat. No. 5,143,054.

TECHNICAL FIELD

This invention relates to a cervical videoscope and particularly to onewith a removable camera unit which allows inspection of the cervix andother body passageways under specific selected wavelength of light andprovides for subsequent treatment of any lesions found. The camera unitincludes a camera, optics and light delivery system, which may also bereferred to as an electronic video endoscope.

BACKGROUND ART

Examination of the cervix for cancer and viral infections are done nowwith a device called a colposcope. This device is a binocular microscopewhich is placed near the patient. It supplies a bright light, (whitelight and green light) and the operator looks through the eyepieces ofthe colposcope much like looking through field glasses. This is donewith a vaginal speculum in place. Some of the devices have cameraattachments for still picture photography. The physician looks at thetissue looking for whitened areas after treatment with 3-54 acetic acid.The acetic acid whitens tissue which is low in raucous, such as cancercells. The physician also looks for clusters of blood vessels which mayindicate new growth such as cancer. The effectiveness of this colposcopyprocedure is only 85%, and this is with a very experienced physiciandoing the procedure. Also, the colposcope is difficult to use because ofits size and weight.

Over the years various vaginal speculae have been developed. Among theseare the following:

Casaneda U.S. Pat. No. 4,210,133 discloses a vaginal speculum having amicroscope mounted thereon which has a light source for illumination andis longitudinally adjustable for focusing.

VanDerBel U.S. Pat. No. 4,597,383 discloses a vaginal speculum havingoptical fiber illumination means attached thereto.

Burgin U.S. Pat. No. 4,638,792 has an adjustable speculum with anincorporated light system.

Walsh U.S. Pat. No. 4,619,248 discloses a light attachment for aspeculum.

Wider et al. U.S. Pat. No. 4,562,832 illustrates in FIG. 6 a fiberopticlight pipe installed in the lower jaw of the vaginal speculum.

Burgin U.S. Pat. No. 4,502,468 has an adjustable speculum with anincorporated lighting system.

Whitman U.S. Pat. No. 3,789,835 discloses an illuminating attachment forvaginal speculum.

Stafl U.S. Pat. No. 4,300,570 has a diagnostic method of projecting theimage of a cervix photograph onto a screen. However, the camera is notmounted to the speculum.

Hasson U.S. Pat. No. 3,789,829 discloses a radium applicator mounted toa vaginal speculum.

Walden et al. U.S. Pat. No. 3,037,505 discloses a speculum with a spraytube carried by a jaw of the speculum.

Tanikawa et al. U.S. Pat. No. 4,461,558 discloses an endoscopicphotographing apparatus applicable to all types of endoscopes and usesthereof.

Toyota et al. U.S. Pat. No. 4,697,210 discloses an endoscope forobserving the interior of a cavity in a human body with the imagedisplayed on a TV screen.

The last two patents are representative of many observation techniquesavailable for use with endoscopes.

None of these devices have served to increase the detection rate ofcancer and the early treatment thereof.

DISCLOSURE OF THE INVENTION

A cervical videoscope apparatus is provided which includes a vaginalspeculum having a first fixed blade, a second blade mounted for pivotalmovement toward and away from the fixed blade and spring means normallyurging the second blade toward the fixed blade. The improvement includesa video camera, optics and light bundle, collectively referred to as anelectronic video endoscope or video camera unit. The video camera unitis removably mounted on one of the blades for viewing the cervix, meansproviding light to the cervix, means for focusing the camera on aselected site on the cervix and means for providing a signal from thecamera to a video screen for viewing the cervix and identifying lesionsthereon. The focusing means may include a track mounted longitudinallyalong one of the blades and means for adjusting the video camera unitalong the track for focusing. The light providing means can include alight carrier on the track for providing light to the cervix. Inaddition, means is provided for selecting light for illumination of thecervix at any one of a range of light frequencies. This can be broadfrequency light, monochromatic light or laser light for illumination. Aparticularly useful light frequency has been found to be from 200 nmthrough 1100 nm. A suitable means for stepping sequentially through thefrequencies is a monochromator. The monochromator converts light from alight source to a single frequency at an output in the form of arectangular slit. A light carrier is provided which includes a bundle ofoptical fibers having a first end in a form of a rectangular collar forreceiving the output from the monochromator and a circular collar at theother end for directing a round column of light onto the cervix.

A laser carrier can be provided on the track for directing a laser beamor laser fiber to vaporize lesions on the cervix. Also, a suction tubecan be provided on the track to remove smoke created when the lesionsare vaporized with the laser.

The invention also provides a method for locating and surgicallyremoving lesions. This method comprises the steps of selectivelyilluminating the cervix with a light of different frequencies, observingthe cervix as it is illuminated with each light frequency, locatinglesions by their florescence or reflectance under one of the selectedlight frequencies and removing the lesions which have been located. Thelesions may be removed by using a laser to vaporize them and theactivation of the laser can be terminated in response to termination ofany florescence at the lesion site.

The video camera unit is removably attached to one blade of thespeculum, as by a flexible strap having a first end fixedly attached tothe first side of the track and extending around the video camera unitand having a second end with means for releasably attaching it to thesecond side of the track. This releasable means may include a pin on thesecond side of the track, an aperture in the second end of the straphaving a diameter just slightly larger than the diameter of the pin soas to be received thereover and a removable fastening means attached tothe end of the pin to hold the second end in place.

After removal from the speculum, the video camera unit can be insertedin an outer, cylindrical, heat sterilizable sheath having a windowsealed to the distal end thereof and an accordian-folded, heatsterilizable, cylindrical sleeve mounted adjacent to the proximate endof the sheath and extendable along the electronic cable and opticalbundle of the video camera unit for a substantial distance formaintaining sterility of the video camera unit within an operating room.Also, means can be provided for releasably locking the video camera unitwithin the sheath in a predetermined orientation. This releasablelocking means may be in the form of a bayonet slot and pin arrangement.The sheath may have a passageway or channel within it for supplying aninsufflation gas to distend the area being examined, along with valvemeans for controlling the flow of gas to the channel. A second channelcan also be provided with a steerable device or other means for carryingout a procedure on a lesion located at the site.

Afterwards, the video camera unit can be removed from the sheath,resterilized or disinfected and reattached to a sterile speculum forexamination of the next patient. The sheath can be thrown away orresterilized for reuse with another patient.

Additional advantages of this invention will become apparent from thedescription which follows, taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of a cervical videoscope constructed inaccordance with this invention and positioned for use;

FIG. 2 is an enlarged rear elevation of the cervical videoscope of FIG.1;

FIG. 3 is a longitudinal section, taken along line 3--3 of FIG. 2;showing further details of the video camera and associated laser tubeand suction tube;

FIG. 4 is a longitudinal section, taken along line 4--4 of FIG. 2,showing details of the track mounting for the video camera unit;

FIG. 5 is an enlarged cross-section, taken along line 5--5 of FIG. 4,showing further details of the video camera unit and track mechanism;

FIG. 6A is a diagrammatical view of video camera unit used inconjunction with a monochromator;

FIG. 6B shows details of the optical bundle connector of FIG. 6A forconverting a rectangular light slit into a circular beam;

FIG. 7 is a diagrammatical view showing the video camera unit used witha band pass filter to provide monochromatic light;

FIG. 8 is a diagrammatical view showing the video camera unit useddirectly with a light source;

FIG. 9 is a fragmentary side elevation of a video camera unit and lightsource attached to the speculum by a releasable strap;

FIG. 10 is an enlarged vertical section, taken along line 10--10 of FIG.9, showing further details of the removable strap;

FIG. 11 is a perspective view of the video camera unit and the sheathinto which it is to be inserted;

FIG. 12 is a fragmentary perspective view showing the video camera unitinserted within the sheath;

FIG. 13 is an enlarged, end view of the distal end of the sheath of FIG.12; and

FIG. 14 is an enlarged vertical section, taken along line 14--14 of FIG.12, showing the interconnection between the video camera unit and thesheath.

BEST MODE FOR CARRYING OUT THE INVENTION

In accordance with this invention a cervical videoscope V is attached toa speculum S, as shown in FIG. 1. In use, the speculum is inserted intothe vagina as shown. The speculum includes a lower fixed blade 10 havinga depending handle portion 12. An upper pivotal blade 14 generallyextends parallel to lower blade 10 and has depending ears 16 at theproximate by which it is pivotally mounted on a support 18. Support hasa yoke 20 at the upper end thereof to which ears 16 are pivoted. Thelower portion of support 18 has a longitudinal slot 22 through which athumb screw 24 extends for tightening against handle 12 to adjust thespacing of upper blade 14 from lower blade 10.

At the pivotal connection between ears 16 and yoke 20 a spring (notshown) may be provided which tends to pivot the upper blade 14 in acounterclockwise direction, as viewed in FIG. 1, so that it is movedtoward fixed blade 10. However, this movement is limited by the positionof nut 26 on threaded adjustment rod 28. Conveniently, rod 28 extendsthrough a lever 30 which is fixedly attached to one of the ears 16 ofupper pivotal blade 14. Thus, when nut 26 is moved outwardly along rod28, blade 14 will pivot toward blade 10 and when nut 26 is movedinwardly along rod 28 blade 14 will pivot away from blade 10.

The videoscope V includes a video camera unit 32 mounted on lower blade10. As previously explained, the video camera unit includes the camera,optics and light delivery system and may also be referred to as anelectronic video endoscope. A longitudinal guide member 34 is fixedlyattached to stationary blade 10, as best seen in FIG. 4. Worm gear 36 ismounted within guide 34, as shown, for rotation about a pin 38. Videocamera unit 32 is provided with a rack 40 extending longitudinallytherealong and attached thereto. The teeth of the rack engage worm gear36. A control shaft 42 is attached to pin 38 and has a knob 44 forrotating worm gear 36 and thereby adjusting video camera unit 32longitudinally along guide 34. This provides a means for focusing thevideo camera unit on the particular area of the cervix which is beinginvestigated. Advantageously, the video camera unit is sealed againstmoisture leakage into the electronics to allow soaking in a sterilizingor disinfecting solution between usage on different patients. It isusually backfilled with nitrogen during manufacture after air andmoisture is removed in a vacuum chamber. A CCD sensor can be used topickup the image and transmit a signal to the video monitor forprocessing. The video camera unit case can be made of titanium-or othermetal which is substantially non-corrosive or it can be made of plastic.The video camera unit can also be sterilized with a gas, such asethylene oxide.

At the forward end of video camera unit 32 is an optical lens system 46for receiving an image from the cervix. This lens system may have zoomcapabilities to provide 2× to 200× magnification. The image is projectedby the camera along cable 48 to a video control unit 50 for projectingan image onto monitor 51 shown in FIG. 6A. As shown in FIG. 6A, a lightsource, such as xeon light source, 52 projects light through amonochromator 54. Other light sources, such as halogen, mercury vapor,mercury arc, incandescent or laser can be used. The monochromator hasthe ability to project light of a single wavelength from the lightsource 52 and to do so in stepped increments. It should have a highoutput with a frequency range from 200 nm to 1100 nm. By this means, aphysician can look at the video monitor while stepping through eachlight frequency and look for fluorescing lesions on the cervix or in thevagina. It has been found that different types of lesions will fluorescein response to different light wavelengths.

The light exits the monochromator 54 through a slit 56 shown in FIG. 6Band enters one end of a bundle of optical fibers 58. Conveniently, oneend of optical fiber bundle 58 is mounted within a rectangular collar 60which mates with the end of monochromator 54 for receiving light fromslit 56. The other end of optical fiber bundle 58 has a circular collar62. Collar 62 and the cable 48 for video control unit 50 connect to acable or light carrier 64 wherein the individual optical fibers 64 arepositioned around the outside of the lens system 46, as best seen inFIG. 5. Thus, the light image of selected wavelength can be directedsubstantially uniformly onto the surface of the cervix or vagina. As themonochromator steps the light from one end of the light spectrum to theother, a wavelength will be encountered in which cancerous lesions orlesions caused by viral infection will fluoresce and therefore will beidentifiable on the video monitor. The florescence of the tissue may benatural fluorescence, or it may be fluorescence produced by substanceswhich selectively enter cancer cells such as hematoporphyrin derivative(HPD).

When this occurs, these lesions can be destroyed by use of a laser beam.This is accomplished by directing the laser bean along an optical fiber66 which extends through a channel 68 attached to guide member 34.Optical fiber 66 can be provided with steering cables (not shown) fordirecting the laser to the lesion cite. A KPT-532 laser, carbon dioxidelaser or a YAG laser having been found to be satisfactory. Conveniently,a suction channel 70 can be provided adjacent to laser channel 68 forremoving smoke caused by destruction of the lesions. This channel may beconnected to a vacuum hose 72, as shown in FIG. 3.

An alternative arrangement is shown in FIG. 7 wherein a removable bandpass filter 74 is provided between the light source 52 and optical fiberbundle 58 for providing selected wavelengths of light to the cervix. Aband pass filter is useful when the patient is treated with a substancewhich will accumulate at the lesion cite and be fluorescent under aknown wavelength of light. In such a case the band pass filter can beselected to transmit only the desired wavelength frequency. Suitablesubstances are hematoporphyrin (HPD) or a derivative thereof, such asdehematoporphyrin either (DHE), corins, pheophorbides and coumerins.Also Rhodamine-123 can be sprayed or painted on the cervix. Finally, thesite can be tagged with a fluorescent tagged monoclonal antibody.

In a still further simplified embodiment, shown in FIG. 8, the lightsource 52 is directly connected to optical fiber bundle 58. Thisembodiment can be used wherein the material at the lesion site on thecervix will have florescence over a wide range of light wavelengths foridentification of lesions.

A number of add-ons may be provided to the apparatus just described.Among these are a character generator for the patient's name, age, etc.,video recorder, video printer and suitable image processors.

A further alternative embodiment is shown in FIGS. 9 and 10 wherein avideoscope V' is removably attached to blade 10 of speculum S by meansof a flexible strap So fixedly attached to one side of rack 40 andextending around the camera unit body and being attached to the otherside of rack 40. This attachment may comprise a threaded stud 82 whichreceives an aperture 84 in the free end of strap 80. This end of strap80 is held in place by means of a removable nut 86.

With this arrangement, the videoscope V' can be used on the speculum Sin the manner previously described. However, the blades of the speculumcover much of the surface of the vagina which prevent thoroughinspection thereof. Thus, by removing the videoscope from the speculumthe scope can then be reinserted into the vagina, as described morefully below so that the areas which were not visible because of thespeculum blades can now be examined.

Conveniently, for use without the speculum, the camera can be insertedinto a sterile sheath H, as best seen in FIGS. 11-14. This sheath H issubstantially similar to that shown in my U.S. Pat. No. 4,878,485 for"Rigid Video Endoscope With Heat Sterilizable Sheath" which issued onNov. 7, 1989. The sheath includes a cylindrical housing 88 having awindow 90 at the distal end thereof and an accordian-folded sleeve 92 atthe proximate end thereof. The housing 88 may be provided with one ormore channels, such as channel 94 which can provide gas under pressureby means of a valve 96 and extends longitudinally through housing 88 andbelow window 90, as shown. Similarly, a second channel 98 can beprovided through which a steerable device 100 is provided.

When the videoscope V' is inserted within sheath H, it can be held infixed position by means of oppositely projecting pins 102 at theproximate end thereof which engage a bayonet slot 104 in an internalsleeve 106 within housing 88, as best seen in FIGS. 12 and 14. Afterinsertion, sleeve 92 can be pulled longitudinally down cable 48 by meansof pull ring 108. Then the sheath and camera can be inserted into thevagina to examine portions which were previously covered with thespeculum. Also, this apparatus can be used for inspection of bodilysurfaces or in the colon and other areas where lesions might besuspected. Conveniently, a passageway 110 is provided along the exteriorof housing 88 through which channels 94 and 98 can extend, as best seenin FIG. 14.

Afterwards, the camera unit can be removed from the sheath, resterilizedand reattached to a sterile speculum for examination of the nextpatient. The sheath can be thrown away or resterilized or disinfectedand reattached to a sterile speculum for reuse with another patient.

From the foregoing, the advantages of this invention are readilyapparent. A simple yet highly useful cervical videoscope has beenprovided which can easily be used by the doctor to exam the cervix andvagina for cancerous lesions or other abnormalities. Also, because ofthe small size of the camera unit there is sufficient space between thecamera unit and the blades of the speculum for inserting forceps andother instruments that may need to be used. By using the cervicalvideoscope in combination with a monochromator the physician can stepthe wavelength of light from one end of the light spectrum to the otheruntil he observes florescence which identifies abnormal cells.Thereupon, he can destroy the cells by use of a laser beam. When heobserves that no more florescence is occurring, then he can discontinuethe operation of the laser, knowing that the lesion has been completelyeradicated. Also, a channel for drawing a suction to remove smokecreated by the destruction of the lesion can be provided. Finally, thecamera is adjustable along a guide on the fixed blade of the speculum tofocus it.

It should also be noted that the device may be detached from the vaginalspeculum and used along with the sophisticated light sources to look forsimilar lesions in the rectal area or on other body surfaces.Conveniently, the camera unit, after removal from the speculum, can beinserted into a sterile sheath in fixed relation therewith. Thiscombined unit can then be inserted into the vagina to examine areaswhich were previously covered by the blades of the speculum. It also canbe used for examining the colon and other areas where lesions aresuspected.

This invention has been described in detail with reference to particularembodiments thereof, but it will be understood that various othermodifications can be effected within the spirit and scope of thisinvention.

I claim:
 1. A method of examining various internal body surfaces forlesions having predetermined characteristics, said method comprising thesteps of:mounting a video camera unit and a source of illumination on ablade of a vaginal speculum, wherein the video camera unit has a cabletrailing from the distal end thereof and the light source has an opticalbundle trailing from the distal end thereof; inserting the speculum intothe vagina of the patient; illuminating the cervix and inspecting it forlesions; removing the speculum from the vagina and removing the videocamera unit and illumination source from the speculum; inserting thevideo camera unit and illumination source into a cylindrical,sterilizable sheath, having a window at a distal end and anaccordian-folded cylindrical sleeve adjacent the proximate end; pullingthe sleeve over the trailing cable and optical bundle; inserting thesheath, with the video camera unit and light source in place into one ormore body passageways to position the video camera unit for viewing aselected site; and examining the site for lesions.
 2. A method, asclaimed in claim 1, including the further steps of:removing the sheathfrom the passageway; removing the sheath from the video camera unit andlight source; sterilizing or disinfecting the video camera unit andlight source; and attaching the video camera unit and light source tothe blade of a sterile speculum for examining another patient.
 3. Amethod, as claimed in claim 1, including the further steps of:removingany lesions found.
 4. A method, as claimed in claim 1, including thefurther step of:supplying insufflation gas through a channel in thesheath to distend the area being examined.